DNA methylation of mesenchymal stromal cells in platelet lysate versus fetal calf serum

Culture medium of mesenchymal stromal cells (MSCs) is usually supplemented with either human platelet lysate (HPL) or fetal calf serum (FCS). Many studies have demonstrated that proliferation and cellular morphology is influenced by these additives – hence they may favor outgrowth of specific subpopulations, thereby affecting the heterogeneous composition of MSCs. We have isolated and expanded human bone marrow derived MSCs in parallel with HPL or FCS for two passages. In HPL the proliferation was significantly higher and cells reflected more spindle-shaped morphology. In contrast, global DNA-methylation profiles did not reveal any significant differences. None of the CpGs revealed significant differences between MSCs that were cultured in HPL versus FCS if the analysis was corrected for multiple testing (limma-adjusted P-value of <0.05). These results indicate that there is no systematic bias for specific subpopulations of MSCs by using either HPL or FCS. Illumina Infinium 450k Human Methylation Beadchip analysis of Mesenchymal stromal cells after 2 passages under HPL or FCS supplementation.